Reciprocating lapping machine for railroad car air brakes



United States Patent US. C]. 51-59 6 Claims ABSTRACT OF THE DISCLOSURE Areciprocating lapping machine for railroad car air brakes, having one ormore stations each provided with parallelly extending spaced apart worksupporting rods between which an abrasive or lapping carrying member isreciprocated in parallel relation with respect to the rods in lappingengagement with the work.

Our invention relates to a reciprocating lapping machine for railroadcar air brakes and has for its principal object the provision of anarrangement for lapping the valve seat of an air brake housing in ahighly eflicient and effective manner.

Among the several objects of the invention is the provision for lappingthe valve seats of a plurality of air brake housings simultaneously.

Another and equally important object of the invention is the provisionfor supporting the air brake housing in an effective and simple mannerduring the lapping of the slide valve seat thereof.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of partsto be hereinafter described and claimed.

The invention will be best understood by reference to the accompanyingdrawings showing the preferred form of construction, and in which: 3

FIG. 1 is a perspective view of the lapping machine embodying ourinvention;

FIG. 2 is a horizontal sectional detail view of the same;

FIG. 3 is a fragmentary perspective view showing an air brake housing inlapping position;

FIG. 4 is a fragmentary sectional detail view taken substantially online 44 of FIG. 2;

FIG. 5 is a perspective view of a lapping block embodied in theinvention.

The several objects of our invention may be accomplished by thepreferred form of construction shown in the accompanying drawings and inwhich there is provided an enclosure or housing having end walls 11, afront wall 12, a back wall 13 to which a cover 14 is hingedly connected.

The front wall 12 has a plurality of openings 15 formed therein in equalspaced relation with respect to each other. Mounted on the bottom wall16 of the housing adjacent the opposite ends 11 thereof, are mountingblocks 17 arranged in pairs and each pair supporting a rod 18. The rods18 are held in fixed position with respect to the blocks 17 by setscrews 19.

Mounted for reciprocation upon the rods 18 are blocks 20 which areconnected to and support a ram bar 21. The bar 21 is fixed to the blocks20 as at 22. Formed in the ram bar 21 are a plurality of equally spacedopenings 23. Projected through each of the openings 15 from the interiorof the housing 10 is a lapping arm 24. The interior end of this lappingarm 24 is reduced and mounted in a slot formed in a yoke 25 and fixedthereto by means of a pin 26. The yoke 25 has a reduced portion 27 whichprojects into the openings 23. Threaded 3,434,243 Patented Mar. 25, 1969into this reduced portion 27 is a threaded bolt 28 by means of which theyoke 25 is fixedly secured to the bar 21.

Adjacent each of the openings 23 there is formed in the ram bar 21 anopening 29 having a threaded plug 30 threaded therein against a spring31, the inner end of which bears against the arm 24.

The outer end portion of the arm 24 carries a head bearing pin 32 whichis adapted to fit in a socket 33 of a lapping block 34 formed of suchmaterial as will effectively serve for lapping purposes. Sucharrangement permits self alignment of the lapping block 34 while inmotion, thus eliminating critical alignment of the air brake housing onthe machine.

Carried by the front wall 12 in spaced relation with respect to eachother and in pairs, are a plurality of worksupporting shafts 35, thepair of shafts being arranged on opposite sides of a lapping arm 24 andin a predetermined relation with respect thereto as may be required bythe workpiece to be lapped. Fixed upon each shaft 35 are a pair of fixedclamps 36 and 37 which, as hereinafter explained, serve to hold the airbrake housing in position during the lapping operation.

The ram bar 21, together with the arms 24 supported thereby, is adaptedto reciprocate in a horizontal-plane. For this purpose, any suitablemeans may be employed for effecting the reciprocation of the ram bar 21and the arms 24. For purposes of illustration, we have shown an aircylinder 38 which may be of any improved construction, including aplunger 39 which is fixed to the ram bar 21 as at 40. This cylinder hasair supply conduits 41 through which air is admitted to the cylinder 38for the intended purpose.

In FIG. 3, we have illustrated an air brake housing 42 mounted inposition on an adjacent pair of shafts 35 with the lapping arm 24projecting therethrough. The shafts 35 project through ports 42' formedin the workpiece. In such position the lapping block 34 will ride in avalve seat 43 as shown in FIG. 3. The clamps 36-37 are of the splittype, wedged together by means of suitable set secrews 35. When thehousing 42 is mounted upon adjacent shafts 35, the outer clamps 37 arepressed against the housing to bear the same against the inner clamps36, at which time the clamps are tightened upon the shafts 35 by the setscrews 35'.

By this arrangement the housing 42 is firmly held in position with thelapping block 34 engaging the valve seat 43 for reciprocation therein toperform the lapping operation.

The lapping block 34 is yieldably held in lapping position within thevalve seat 43 by the spring 31. By adjustably threading the plug 30against the spring 31, the amount of yieldable pressure exerted on thelapping arm 24 may be controlled.

When certain of the arms 24 are ineffective by reason of the fact thatthe adjacent shaft 35 do not support thereon workpieces, to prevent thearms 24 from rubbing against the wall 12, they are supported free of thewall 12 by means of adjustable fiber washers 44 (as seen in FIG. 4) thewasher 44 being eccentrically connected as at 25 to the wall 12. Theposition of the shafts 35 on opposite sides of the arm 24 may berelocated by positioning such shafts in openings 46 provided in thefront wall 12, as seen in FIG. 1.

From the foregoing it is apparent that we have provided an effectivemachine for lapping the slide valve seat of an air brake housing, themachine being constructed so as to handle one or more of such housingsduring a single operation. There are relatively few parts involved inthe construction, which affords manufacture at an economical cost.

While we have illustrated and described the preferred form ofconstruction for carrying our invention into effect, this is capable ofvariation and modification without departing from the spirit of theinvention. We therefore do not wish to be limited to the precise detailsof construction set forth, but desire to avail ourselves of suchvariations and modifications as come within the scope of the appendedclaims.

Having thus described our invention, what we claim as new and desire toprotect by Letters Patent is:

1. A lapping machine of the class described comprising (a) a pluralityof lapping stations,

(b) each station comprising a pair of work-supporting shafts extendingin parallel relation with respect to each other,

(c) means for removably clamping a workpiece to said shafts,

(d) a lapping bar extending approximately parallel to said shafts andhaving a reciprocal lapping element carried adjacent the outer end ofsaid lapping bar in lapping engagement with said workpiece,

(e) means for reciprocating said lapping bar relative to the shafts.

2. A lapping machine of the class described comprising (a) areciprocatory ram bar,

(b) means for supporting said bar for reciprocation,

(c) a plurality of arms carried by and extending from said bar insubstantial parallel relation with respect to each other andsimultaneously reciprocated with said bar,

(d) a lapping element carried by each of said arms adjacent the outerend thereof,

(e) means disposed on opposite sides of each of said arms in approximateparallel relation with respect to each other for supporting a workpiecehaving a slide valve seat,

(f) said lapping element being adapted to lappingly engage said seatduring reciprocation of said arms by said bar.

3. The lapping machine defined by claim 2 wherein the means forsupporting the tram bar comprises a pair of reciprocating blocks, asupporting shaft for each block, and standards supporting said shaft.

4. The lapping machine defined by claim 2 wherein the lapping elementcomprises a lapping block having a socket formed therein and ahead-bearing pin carried by each of said arms and projecting into saidsocket to permit the block to self-adjust itself relative to the surfaceof said valve seat.

5. The lapping machine defined by claim 3 wherein the lapping elementcomprises a lapping block having a socket formed therein and ahead-bearing pin carried by each of said arms and projecting into saidsocket to permit the block to self-adjust itself relative to the surfaceof said valve seat.

6. The lapping machine defined in claim 2 characterized by the inclusionof spring means acting on said arms to yieldably urge the lappingelement into lapping engagement with said valve seat.

References Cited UNITED STATES PATENTS 1,246,191 11/1917 Vocelle 51-34.61,780,288 11/1930 Yerk et a1 51--245 X 2,266,113 12/1941 Wiss 51-245 X2,757,488 8/ 1956 Greenberg 51-34.3 2,787,867 4/ 1957 Klein 51-343 JAMESL. JONES, JR., Primary Examiner.

US. Cl. X.R. 5134, 245

